Method of distilling hydrocarbons and producing coke and product thereof



J. D. FIELDQ 1,864,720 RODUCT THEREOF June 28, 1932.

METHOD OF DISTILLING HYDROCARBONS AND PRODUCING COKE AND P Filed June 29 Patented June 28, 1932 UNITIED'STA'IE'EST PATENT OFFICE JOHN D. FIELDS, OF IiOS ANGELES, CALIFORNIA mn'rnonor D-IS'I'ILLING HYDROOARIBONS AND Pnonucme COKE AND raonuc'r THEREOF Applicationflled June 29,

- This invention resides in the provision of a method of distilling hydrocarbons partlcularly the petroleum group, together wlth solid cellulosic vegetable matter and a ferrous material for the purpose of producing low boiling and other desirable oil fractions, anda hard strong residual coke-and other useful products.

- An object of the invention is to provide a me hod of the character described which may be readily and economically carried out in a particularly efiicacious manner to obtain in a single operation a comparatively great yield of low boiling and other petroleum fractions and a residual ferruginous carbon or coke, having properties enabling its complete and easy removal from the still and rendering it of great value as a fuel and reducing agent in metallurgical andother operations.

Anotherobject is to produce with a method of the character described a hard ferruginous coke, characterized by constituents and properties of carbon derived both 'from the vegetable matter and the petroleum and having a high tensile and compressive strength,

whereby the product is particularly well suited for use in blast furnaces.

With the foregoing objects in view, together with such other objects and advantages as may subsequently appear, the invention hereof resides in the steps and features hereinafter set forth and claimed,-but it is to be understood that variations in said method may be resorted to within the scope of claims herewith appended.

In carrying out the method of this invention, comminuted iron ore, finely divided vegetable matter and a petroleum hydrocarbon are placed in a suitable still and subjected to such temperatures and pressures as will effect the distillation of said substances and the formation of residual ferruginous coke as will be herinafter more fully explained.

Theiron ore before addition to the other substances is reduced to such a state of pulverization or fineness that when added to said substances will be held in suspension by the vege able matter, a fineness of from 150 to 200 mesh having been found satisfactory.

1931. serial-m). 547,795.

The organic or vegetable matter is also finely divided and may consist of various substances capable of givingalcohol, acetic acid, acetone and phenols when subjected to destructive distillation. Kelp, beet pulp, sugar cane waste, saw dust and other solid carbohydrate or cellulosic vegetable refuse and substances of similar character are satisfactory, but any vegetable matter capable of being converted into charcoal may be utiw lized. Vegetable matter ina green or natural state (i. e. containing a substantial percentage of water) is preferable. The vegetable materials above listed consist largely of cellulose or other solid carbohydrate material and 55 are relatively poor in proteins, and are substantially free from sulphur. Such vegetable materials are hereinafter included in the expression a cellulosic vegetable matter.

Vegetable materials having these character- 1 istics are generally preferred in the process, since they tend to give good coke.

The hydrocarbon may be of any character desired. However, :a particular hydrocarbon which may be employed, is one, for example comprising petroleum having a high boiling point, say of approximately 600 degrees Fahrenheit (315 C.) and of eitherasphalt or paraflin base.

It should be noted that the iron ore, vegeso table substance and hydrocarbon may be combined in various proportions dependent on the characteristics of said substances and the nature of the products thereof desired.

A suflicient amount of thepetroleum oil is always employed-so that (at temperatures well above the liquefying point of the oil) the mixture of the oil, sawdust or other comminuted vegetable matter used, and iron ore, is a liquid mass. It is to be understood that the oil itself may be freely liquid, semi-solid or even solid at normal room temperature or at some lower temperature. However, a specific proportion is 10 parts of ironore, 10 parts of vegetable substance (say green wood 96 sawdust) and 80 parts of a petroleum hydrocarbon.

In such an example, the combined amounts of the vegetable matter (e. g. sawdust) and iron ore, represent only a minor fraction of 100 the amount of the hydrocarbon. Further the proportions of vegetable material and iron ore, as given in this example are about the maximum which I would recommend under any circumstances.

Such a mixture as here described is (at least when hot) a freely liquid mass, which flows as a liquid and can readily be handled as a liquid, by means of a centrifugal pump or the like, and is not a paste or a solid material slightly moistened with an oily liquid.

In distilling the mixture of said substances, various pressures and temperatures may be used provided such temperatures and pressures are sufficient to carbonize or char the said vegetable matter, separate the low boiling fractions and reduce the residuum to a ferruginous coke. A temperature of from 350 to 400 degrees Centigrade (or 662 to 752 F.) has been found suflicient but higher temperatures may be used where heavier fractions are to be produced. As to the pressures, a pressure of 100 pounds per square inch with a temperature of 400 C. has proven satisfactory, although variations of the pressure may be resortedto as desired.

Upon heating the mass sufliciently to produce destructive distillation of the vegetable matter (the iron ore and hydrocarbon being present), the volatile products such as essential oils and acids from the vegetable mat-' ter and the low boiling fractions of the hydrocarbon will distill over, the liberation of the gases and vapors agitating the mass. Petroleum distillates are formed during the operation contemporaneously from both the vegetable matter and the hydrocarbon, which distillates will pass off together. The distillates are treated inthe usual manner to effect the separation thereof, into desired products.

Distillation treatment is continued until solid coke remains in the still, and the hydrocarbon and vegetable substances are reduced to a solid, including organic carbon or charcoal derived from said vegetable substance and carbon derived from the decomposition of petroleum hydrocarbons which may also contain other substances.

This residual solid product of distillation, is, generally speaking, a hard black coke having a high tensile and compressive strength. Such a product is considered of great value in blast furnace operations yet is useful for many other metallurgical and for any of the purposes fo'r'which coke is commonly used.

It is important to note that owing to subjecting the mixture aforesaid to the previously qualified distilling temperatures, in one operation, a quantity'ofresidual charcoal is formed from the vegetable matter before the formation of mineral to carbon (petroleum coke), with the result that a protective layer of such charcoal is deposited on the inner surface of the still. In this way, adhesion of the mineral carbon residuum, which would result if the mineral carbon came into intimate contact with the interior surface of the still, is eliminated and the whole mass of coke may therefore be readily removed from the still. The coke does not rigidly adhere to the still bottom, as does the petroleum coke formed in the' usual oil cracking stills. This property is hereinafter referred to in stating that the coke is non-adhesive. As is well known petroleum coke as usually heretofore prepared adheres tenaciously to the bottom 'and sides of the still (see economic paper 9,

U. S. Bureau of Mines, pages 28-29);

' To insure this action and to prevent the particles of iron ore from precipitating to the bottom of the mass during the distilling operation, the fine ore is thoroughly admixed with the finely divided vegetable matter pre- The said ferruginous particles being held in suspension during the distilling action will remain thoroughly distributed throughout the body of coke as the latter forms in the bottom of the still, thus rendering the formed coke highly heat-conductive so that it will serve to protect the walls of the still against burning out during the final stages of drying out the coke, and whichalso serves to hasten the driving ofi of the final volatiles from the coke residuum. The heating is preferably continued to leave dry coke in the still.

The process can be carried out in an apparatus such as shown in the accompanying drawing, in which Fig. 1 shows a side elevation, partly in section, of the essential parts. Fig. 2 is a section, on the line 22 of Fig. 1, the connections being omitted.

A represents a boiler or still, heated by fire in the fire place B, heated in any convenient manner, as by oil or gas burner B. A mixture of sawdust and iron ore is fed from the bin C through the tube E. Petroleum oil from overhead tank D, flows through valved pipe F. The oil, sawdustand iron ore flow into the still or boiler A, to fill the same to the desired level. The several pipes are provided with suitable valves.

On heating the mixture,- the vapors evolved pass through pipe G to condenser H, and are therein condensed.

The vapors, on leaving the still A, pass up through a tower or dephlegmator I, wherein heavier fractions may condense and fall back into the still. At J is shown a temperature indicator and at K is a pressure gauge.

At P is shown an automatic pressure valve which allows the vapors to pass to the condenser, only so long as the pressure in the outlet of I is above some predetermined amount,

for example 100..lbs.

As shown in Fig. 2, a thin layer of the charcoal is formed at M, while the bulk of the ferruginous coke containing some charcoal is supported thereon, as shown at L.

A manhole N is provided for removing the coked residue from the still at the end of the process.

It will now be seen that by the simple and inexpensive expedient of adding small amounts of a solid cellulosic vegetable substance and the iron ore to petroleum to be distilled to the point of substantially complete coke formation of the still residuum, I am able to produce in one continuous operation improved distillates and low boiling fractions and also a valuable carbon or coke including the heretofore bothersome and more or less useless still residuum, the easy and clean removal of which from the still is also made possible by suchadditions.

I do not restrict myself to the proportions as given, but I preferably use, in all cases, oil in amount much greater than the vegetable material and much greater than the iron ore.

The coke formed is, as stated above highly suitable for blast furnace operations. It is even superior to good grade coal coke, which ordinarily contains around 10 to 12% of siliceous ash. My coke product is about as strong as good grade coal coke as commonly now used in blast furnaces.

Cracking still coke and coking still coke as heretofore commonly made, are all soft, i. e. they have no substantial compressive strength or tensile strength. These cokes also are high in volatile matter, say 8 to 12%, usually around 10 to 11%. Cracking still coke from any of the prior processes, is very largely (7 580%) fines, and the lump coke is very weak. This material has heretofore been used to some extent, for making electrical carbon (after. suitable refining) or for a reducing agent (in various chemical or metallurgical processes) but the great bulk of the cracking still coke has been used as fuel under the stills. Cracking still coke and coking still coke are both very variable in sulphur content, depending on the original oil being treated, and inmost cases the petroleum coke of the prior art contained between 1.5 and 4% S. average about 2% S. For most metallurgical purposes, coke containing over 1% S. will not be accepted.

Refined coking still coke usually contains below 1% S. and is generally below 1.5% (sometimes below 1%) volatile matter. It has not sufficient strength to be usable in blast furnaces (for which purpose it of course could not be used commercially on account of the cost).

Gokingstill coke, although obtainable in the form of lumps, contains so much volatile matter that it cannot. be heated without softlening and running somewhat like cannel coa volumes of smoke.

The addition of the iron ore is to harden the coke formed. This of course increases the ash contentof the coke, but iron in the coke is not objectionable in metallurgical processes, nor in most of the other uses of coke, except in the manufacture of electrical carbon. v h

This application is in part continuation of my copending application 432,910, filed March 3, 1930.

When burned it produces great the process of cracking petroleum and producing coke, by mixing a small proportion,

say 15-20% of cellulosic material (wood sawdust, etc, as herein described) but without the addition of the iron ore and heating the mixture as in the present disclosure, as well as the coke product formed. Such coke formed is not so hard and strong as the coke produced when the iron ore is added, as in the present case.

- I claim:

1. The method consisting in distilling a petroleumhydrocarbon to coke, in the presence of a solid cellulosic vegetable substance, and iron ore, the petroleum being initially in amount greater than either of the other materials. i

2. The method consisting in adding amineral oil to a much smaller amount of a mixture of comminuted solid vegetable matter of very low proteincontcnt and finely divided iron ore, and effecting cracking distillation of said mixture, with coke formation.

3. The method consisting in mixing an excess of mineral oil and a mixture of comminuted solid vegetable matter and finely divided iron ore in such proportion as to form a pumpable fluid oily mass and effecting a distillation of such mixture to the point of coke formation.

4. The method which consists in sub'ecting a liquid pumpable flowable mixture 0 petroleum, finely divided iron ore and comminuted solid cellulosic vegetable matter to distillation at a sufiicient temperature and under a mass to a temperature suflicient to drive off the volatiles of the mixture and form a dry hard carbon residualcontaining mineral and vegetable carbon.

6. The method consisting in subjecting not over one part of a mixture of comminuted iron ore and a vegetable substance in a, green or natural state mixed with at.least four parts of a liquid petroleum residuum, to distillation at temperatures and under pressures sufficient to release the distillates and low boiling fractions from the mixture, then continuing the heat and pressure treatment of the mixture to the extent necessary to effect cracking of the oil with coke formation to form a hard ferruginous coke product.

7. The method of converting the residuum derived from the distillation of petroleum into a coke of high tensile and compressive strength, consisting in distilling several parts of the petroleum residuum together with only one part of a mixture of an iron ore and a vegetable-cellulosic substance thatis reducible to charcoal when subjected to the temperatures employed in the coke-forming distillation of the petroleum.

8. The method consisting in admixing finely comminuted iron ore with comminuted solid vegetable matter, adding one part of the mixture to several parts of petroleum and subjecting the mass to temperatures sufficient to drive off volatiles and to produce a a hard dry coke of high heat conductivity.

9. A process of making hard coke during the cracking and distilling of petroleum oil, which comprises mixing relatively small amounts of solid comminuted cellulosic vegetable material, and iron ore, with a relatively larger amount of a petroleum oil, and heating the mixture in a still to crack and distill the oil, and carrying the distillation to coke formation.

10. A process which comprises well mixing comminuted woody material and finely powdered iron ore, adding such mixture to a substantially larger amount of a petroleum oil which contains high-boiling fractions, heating a bulk of such mixture in a still, while under superatmospheric pressure during a part at least of the heating operation, and continuing the heating past the stage of forming charcoal from said woody material, to the stage of coke formation.

11. A process of simultaneously making hard coke and a distillate containing gasoline, which comprises mixing solid cellulosic vegetable matter yielding aliphatic organic com- I pounds on destructive distillation, with pctroleum hydrocarbons and iron ore, in such proportions as to form a liqiud oily mass capable of being pumped, and heating the mixture in a still to distill ofl' light hydrocarbon oils from the petroleum hydrocarbons, while simultaneously distilling off volatile mate als from the said vegetable matter, which 12. A process of simultaneously making.

hard coke and a distillate containing gasoline, which comprises mixing relatively small but substantial amounts of woody material and added iron oxide with petroleum hydrocarbons, and heating the mixture in a still to distill off the petroleumhydrocarbons while simultaneously distilling off volatile compounds from the said woody material, which distillation products are adapted to be blended to produce a gasoline containing distillate, and continuing the distillation until a hard coke containing vegetable carbon which does not stick to the metal walls of the retort, is produced.

13. The method of simultaneously producing petroleum distillates and high grade coke which comprises subjecting a mixture of several parts of petroleum and one part of a composition containing comminuted solid vegetable matter consisting largely of carbohydrate which on heating will char in the solid state, mixed with added iron oxide, to cracking and destructive distillation and continuing the process sufliciently to form a solid mass of coke.

14. Theinethod of simultaneously producing petroleum distillate and high grade coke which comprises subjecting a mixture of one part of comminuted woody material and iron ore and several parts of a petroleum oil, to cracking and destructive distillation with coke formation condensing the vapors evolved and recovering a ferruginous petroleum coke containing charcoal from said woody material. a

15. The method of simultaneously producing petroleum distillate and high grade coke which comprises subjecting a mixture of one part of a mixture of iron ore and comminuted solid carbonizable carbohydrate vegetable matter and several parts of a petroleum oil to heat under superatmospheric pressure, the heat being sufiicient to carbonize the vegetable matter and to crack the petroleum oil and form coke therefrom, condensing the distillate and recovering a petroleum coke containing vegetable carbon.

16. The method of simultaneously producing oil distillate and high grade coke which comprises subjecting a mixture of one part of a mixture of iron ore with comminuted Woody matter and at least four parts of petroleum hydrocarbon oil while under superatmospheric pressure, to the influence of heat suflicient to carbonize the woody matter and to crack the hydrocarbon oil with coke forrecovering a ferruginous petroleum coke containing vegetable carbon.

17 The method of simultaneously producing petroleum distillate and high grade coke which comprises subjecting a mixture of one part of a mixture of iron ore with fine solid carbonizable carbohydrate vegetable matter and several parts of a high boiling petroleum oil to a temperature between about 350 and 400 C. while under a pressure of approximately 100 pounds per square inch, condensing the evolved vapors and recovering a strong ferruginous petroleum coke containing vegetable carbon.

18. The method of simultaneously producin" petroleum distillate and high grade coke w ich comprises subjecting a mixture. of a high boiling petroleum oil, with iron ore and comminuted woody matter, in such proportions as to form a flowable mass, to a temperature between 350 and 400 (1., and under superatmospherie pressure of several atmospheres, condensing the evolved vapors and recovering a strong ferruginous petroleum coke containing vegetable carbon.

19. The herein described process which comprises subjecting a liquid flowable mixture containing a high bo1lin petroleum oil with a substantial but minor raction only of its weight of a mixture of fine solid carbonizable carbohydrate vegetable matter and iron ore, while under superatmospheric pressure, to heat at least suflicient to destructively distill said vegetable matter, and condensing the vapors evolved, and continuing the distillation sufiiciently to leave a solid mass of coke-like solid material.

20. The herein described process which comprises subjecting a liquid flowable mixsure, to heat at least sufiicient to destructively distill said sawdust, and condensing the va-. pors evolved, and continuing the distillation sufficiently to leave a solid mass of coke-like solid material.

21. The herein described process which comprises subjecting a liquid fiowable mixture containing a high boilin petroleum oil with a substantial but minor fraction only of its weight of a mixture of comminutcd kelp and iron ore, while under superatmosphcric pressure, to heat at least sufiicicnt to destructively distill said kelp, and condensing the vapors evolved, and continuing the distillation sufliciently to leave a solid mass of cokelike solid material.

22. A ferru inous petroleum coke made by distilling to co e a liquid flowable mass of not over one part of a mixture of vegetable eel.- lulosic matter and iron ore and at least four parts of mineral oil residuum, and which coke does not adhere to the walls of the still.

A ferruginous petroleum coke, made by distilling to coke, under superatmospheric pressure, a liquid fiowable mass of a small I said vegetable material.

JOHN D. FIELDS. 

